We use the Microsoft Windows-based 3CX Phone System, which requires no proprietary equipment and can be installed either on existing server hardware or hosted in the cloud. Designed for flexibility, the 3CX system allows users to make calls straight from their computer, or from anywhere using a remote extension. 3CX also provides users with traditional phone functionality, such as office phone numbers, voicemails, and faxes. Because no proprietary equipment is required, there is no vendor lock-in when choosing handsets or softphones.